ID 2880 -
Witamina K
PL: Witamina K
EN: Vitamin K
Pdf: vitamin K2
1. Charakterystyka żywności / składnika
The food constituent that is the subject of the health claim is vitamin K (i.e. phylloquinone and menaquinone) which is a well recognized nutrient and is measurable in foods by established methods.
Vitamin K is a family of structurally similar, fat soluble, 2-methyl-1, 4-naphthoquinones, including phylloquinone (2-methyl-3-phytyl-1,4-naphthoquinone, vitamin K1) and menaquinones (collectively known as vitamin K2). Menaquinones are a large series of compounds containing an unsaturated side chain with differing numbers of isoprenyl units at the 3 position in the methyl-1,4-naphthoquinone nucleus. Depending on the number of isoprenyl units, the individual compounds are designated as menaquinone-n-(MK-n). Phylloquinone (vitamin K1) is found in higher plants and algae, with the highest concentration in green leafy vegetables. Menaquinones (vitamin K2) occur naturally in foods and can also be produced by many bacteria.
Phylloquinone and menaquinones are naturally present in foods and phylloquinone has been authorised for addition to foods and for use in food supplements (Annex II of the Regulation (EC) No 1925/20064 and Annex I of Directive 2002/46/EC5). This evaluation applies to vitamin K naturally present in foods and to the form authorised for addition to foods and for use in food supplements (Annex II of the Regulation (EC) No 1925/2006 and Annex II of Directive 2002/46/EC).
The Panel considers that the food constituent, vitamin K, which is the subject of the health claim, is sufficiently characterised.
2.3. Funkcjonowanie serca i naczyń krwionośnych (ID 124, 125 2880)
The claimed effects are “cardiovascular health”, “vascular health”, and “heart health”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel notes that the claimed effects relate to the normal function of the heart and blood vessels.
The Panel considers that the normal function of the heart and blood vessels is beneficial to human health.
3. Naukowe uzasadnienia wpływu na zdrowie człowieka -
Proteins containing γ-carboxy-glutamic acid (Gla) residues are known to be dependent on vitamin K for their synthesis. These include (but are not limited to) the plasma clotting factors II, VII, IX, X; proteins S, C and Z (which play an anticoagulant rather than a procoagulant role in normal haemostasis); and osteocalcin and matrix Gla protein (MGP), which are abundant in bone and appear to play a role in the control of tissue mineralisation and skeletal turnover.
Vitamin K status is determined through measures of the ratio of carboxylated to non carboxylated vitamin K – dependent proteins.
3.3. Funkcjonowanie serca i naczyń krwionośnych (ID 124, 125, 2880)
Vitamin-K dependent proteins have been identified in vascular tissue, including a matrix Gla-protein (MGP). In a MGP knockout mouse model, spontaneous calcification of soft tissues (mostly arteries) occurs (Luo et al., 1997). In the Keutel syndrome, due to a mutation of the gene encoding the human MGP, patients display several of the same features as the knockout mice, including abnormal calcification of cartilage of ears, nose, and respiratory tract. However, they do not appear to have increased incidence of coronary arterial disease or rupture of abdominal aortic aneurysm (Munroe et al., 1999).
The health claims (ID 124, 125 and 2880) are made on vitamin K2. From the literature available, four papers refer to the role of vitamin K from all sources and/or vitamin K2 in relation to the heart and/or blood vessels (Jie et al., 1995; Maas et al., 2007; Geleijnse et al., 2004; Beulens et al., 2009). The Panel considers that studies investigating the relationship between vitamin K intake (from all sources and/or as vitamin K2) and arterial calcification or the elastic properties of the arteries (which may interfere with normal vascular structure and function) are pertinent to the claimed effect.
Three cross-sectional studies investigated the relationship between vitamin K intake and arterial calcification in women. Whereas one study found lower vitamin K (mainly vitamin K1) intakes in women with aortic atherosclerosis (Jie et al., 1995) as compared to controls, another study reported that vitamin K2 (but not vitamin K1) intake was inversely related to the presence of coronary calcification (Beulens et al., 2008), and the third showed no association between either vitamin K1 or vitamin K2 intake and breast arterial calcification after adjustment for confounders (Maas et al., 2007).
An observational prospective study in 4,807 older men and women found that high intakes of vitamin K2 (but not of K1) were associated with a significantly lower degree of aortic calcification and lower incidence of coronary heart disease after adjustment for confounders (Geleijnse et al., 2004). The Panel notes that no definite conclusion can be drawn from this single prospective study on a causal link between the intake of vitamin K2 and the normal function of the heart and blood vessels.
In weighing the evidence, the Panel took into account the inconsistency of the results reported in three cross-sectional studies, and that no definite conclusion can be drawn from a single prospective study on a causal link between the intake of vitamin K2 and the normal function of the heart and blood vessels.
The Panel concludes that the evidence provided is insufficient to establish a cause and effect relationship between the dietary intake of vitamin K2 and the normal function of the heart and blood vessels.
5. Warunki i możliwe ograniczenia stosowania oświadczenia
The Panel considers that in order to bear the claims a food should be at least a source of vitamin K as per Annex to Regulation 1924/2006. Such amounts can be easily consumed as part of a balanced diet. The target population is the general population.
Warunki i możliwe ograniczenia stosowania oświadczenia
Products containing a minimum of 15% of the vitamin K Reference Labelling Value (which is 75 micrograms for adults and 12 micrograms for children 6 months to 4 years of age) would be permitted to carry the claim (i.e., products intended for adults must contain a minimum of 11 micrograms MK-7 per 100 g or 100 mL, while products intended for children must contain a minimum of 2 micrograms per 100 g or 100 mL).